We stayed in the Trastevere neighborhood in Roma for 6 days and thought it was a great location.
Tons of restaurants open all day/night.
Easy walk to the Pantheon area and other tourist sites. We walk 4-5 miles a day.
What is the equivalent neighborhood in Madrid?
You can try Malasaña or Lavapies
La Latina is probably the closest. Maybe Malasaña, but that might border on too young/trendy.
These also align with my general recommendation that visitors avoid accommodation that's an area loosely drawn by Gran Via to the north, then roughly connecting the Royal Palace, Plaza Mayor, Sol.
La Latina, that is, anything close to Cava Bava st, a short st with 45 bars. Number of bars in the neighborhood: 250
